Conventional agricultural combines include a header assembly for severing and collecting crop materials as the combine is driven through a field and a feeder mechanism for advancing and elevating the crop materials to a threshing area on the combine. In the threshing area of the combine, crop material is threshed as it passes between a rotor assembly and a stationary generally cylindrical housing.
The rotor assembly of the combine includes an elongated cylindrical drum or rotor mounted for rotation about a fixed axis. A plurality of thresher elements are fixed to an outer wall of the rotor. The thresher elements impact with the materials and act in combination with the cylindrical housing in separating edible grain or seed from the material other than grain or seed. Various cleaning systems further facilitate the separation of materials.
In rotary threshing, different rotor assembly configurations have been customarily used to harvest different crops. For example, when small grain, corn, and soy beans are harvested, a rotor assembly is typically configured with helical arrays of thresher elements at a forward end of the rotor and linear arrays of thresher elements extending rearwardly from the helical arrays. Harvesting of rice, edible beans, and damp wheat crops normally requires a different rotor assembly configuration. When the configuration of the rotor assembly is mismatched to the particular crop material being harvested, an inefficient waste of materials, frequent jamming of the rotor, and extended downtime for the combine can result.
At a collection station, farmers are paid a premium price for crop material having a relatively low damage content by volume. As small a change as 0.1% in crop material damage by volume can greatly affect the price a farmer is paid for his crop. Accordingly, there is a need and a desire for a combine capable of harvesting material with a minimum of damage to the harvested materials.
U.S. Pat. No. 5,035,675 to N. C. Dunn, et al. discloses a convertible rotor assembly which has advanced combine harvesting technology. This rotor assembly includes a rotor configured to allow a plurality of thresher elements to be arranged thereabout and longitudinally therealong in various patterns and arrays.
The ability to readily change the thresher element configuration about the circumference of the rotor readily allows a farmer to adapt the combine to the particular material being harvested thereby facilitating the threshing process and reducing grain damage. Thus, not only is the combine more efficient but a reduction in grain damage allows the farmer to realize a premium price for his crop thereby maximizing his profits.
During a harvest, a forward end o the rotor assembly receives a greater amount of unthreshed crop material than does a more rearward section of the rotor assembly. Thus, there is a need and a desire to configure the thresher elements in a pattern which will advantageously handle the abundance of material at a forward end of the rotor assembly while simultaneously providing an efficient threshing action thereto.